Overall objectives: (1) To determine steroid binding levels (particularly, of progesterone, cortisol, estradiol, and testosterone) in the uterus, breast, and serum of individual cancerous and non- cancerous patients. (2) To relate, if possible, the steroid binding levels to the endocrine status of the patient and to the biological characteristics of the tissue under study. (3) To partially purify the steroid-binding proteins (from pooled tissue specimens) for physicochemical characterization with respect to steroid ligand specificity, equilibrium constant for steroid-protein complex formation, and molecular size (Stokes radius).